Improvement in bridges



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Letters Patent No. 107,576, dated September 20, 1870.

IMPROVEMENT IN BRIDGES.

The Schedule referred to in these Letters Patent and making part of thesame.

To all lwhom it may concer-n Beit known that I, ISAAC H. WHEnLnR, ofScioto-l ville, in the county of Scioto and State of Ohio, have yinvented a new and useful Improvement in Bridges; and I do herebydeclare that the following is a full, clear, and exact descriptionthereof',l which will enable others skilled in the art to make and usethe same, reference being had to the accompanying drawing forming partof this specitication.

My invention relates to wooden bridges, and has toi" its object torender unnecessary a large amount of the material now used, to removefrom the bridgev a great deal of dead weight, and to reduce the cost ofconstruction.

My invention consists in combining wit-h the upper, lower, and middlechords, diagonal ,truss and short braces, as hereinafter specified.

Figure l represents a longitudinal sectional elevation of a bridgeconstructed according to my improved plan;

Figure 2 is a plan view,'partly broken out and Figure 3 is a transversesectional elevation of the same.'

A represents the lower chords;

B, the upper chordsyand C, the intermediate chords, which I propose tointroduce. Y

D represents the posts; l

E, the diagonal truss-braces; an

F, the short braces, which I introduce between the lower and middlechords and the middle and upper chords.

The top laterals, I, cross each other above the ties- K and at the sidesof the chords, and one of each of the crossing-braces is gained into thetop of the chord,

as shown in the plan viewat L.

The-braces are also bolted down to the cross-ties by braces, M, allmaking a very strong connection.

The posts D and trusses E aregaiued into the sides i 'of' the lower andmiddlechords, and bolted together' by bolts, N, in a way to make thelabor of const-ruction very simple, and much less than in other bridges.

The span may be made very much vlarger by this improved arrangement, thesingle truss having .a capacity to sustain spans of one hundred andseventyive to two hundred feet, while two' hundred and fifty to threehundred feet may be safely spannedwith the double truss. There is nodead or useless timber in it. Every piece of timber used is a brace orsupport to the whole, in some material way,'and the heaviest iron usedin common road-bridges are tlneefquarter inch bolts, andbut few ofthese.

Having thus described my invention, l claim as new and desire to secureby Letters Patent- In wooden bridges, the combination of chords A B fXVitnesses:

C. LEVY, T. A. SOWEL.

